OK, here is how Mozilla/Thunderbird LDAP works with Exchange 2000-2003:

1. The default LDAP port for Active Directory is 3268 (not 389) so make sure you've got this port open thru the firewall, and make sure to configure it in your LDAP account settings in Mozilla/Thunderbird.

2. For Base DN, you MUST enter something like dc=yourdomain,dc=com (whereas Outlook Express lets you get away with putting NULL).

3. For Bind DN, you must enter a domain user which has permission to search the directory. You should enter it qualified by the NetBIOS domain name, for example: mydomain\username

4. For some reason, Thunderbird doesn't always seem to recognize that it needs to log on before querying. The easiest, most reliable way I have found to force it is to go to the Offline tab in the Directory Server Properties and click the Download button. This function seems to "see" that Active Directory wants a logon, so Thunderbird will display the logon

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